Cotton cleaning apparatus



s- 9 D. D. DAY 2 2,948,022

COTTON CLEANING APPARATUS Filed Feb. 14, 1958 2 Sheets-Sheet 1 LIA T Bil/Vii) Fl Uf M I j o 1 5 8w Aug. 9, 1960 D. D. DAY

COTTON CLEANING APPARATUS 2 Sheets-Sheet 2 Filed Feb. 14, 1958 2948,022 corrou 1; Kim MUs Dewey D. Day,;Balla's, Ten, assigno'r -to The Murray qmpany of Texas, -Ine., Dallas, Text, =-a corporation of Delaware This invention relates to when o'leatning se arate n11, forexample, inclean'ihg lintcottonpreji artery to its "delivery to a ba'ling press. As a particular ihstance of its *u'tilit y, "i't'may he emplo ee as a *means for removing 'la por'tion, atd'eastgof therlirtand trash trdmesttun-whieh 'vvas nledhanically picked, and which-contains more ha ergn material tha n hand-piickedcot'ton, the apparatus being as installed as to "re'ceivethe airborne liht'frorh Jan vidual rn she to deliver the clean hat to a fhattery denser which in turn delivers the lint to a hailingpress. The press invention is "in the nature of an imifirovenient t e meanin a pmms 'disclosedfin the "cbp'ehding United States -'apfiiic"ation, satin No. 4811125, filed by Dewey tapas en sanitary 11,1955, saw us. Patent Number ilgfi 30,3 28 Like the device dffthe shave applicamn, the 'c fearre'r of the presefit iiivention is at the kind which is so designed tl iatsubsitafitiallyfiall cifthe-Iint conveying airis 'separatedfrom the lint he'f re the iat'te'r delivered to the cleaning tnstrumenmities, and "which comprises means "for subjecting the lint to a or carding action by mea s including a'toothed eyhhaer, 'a toothed rotary feeding roll, .and one "or more grid or stripper bar's operative-to separate dirt and tr'ash from the dint fibers as the latter are whipped past "the bar 'vvhile adhering to the teeth of the rapidly turning saw cylinder. While in the above application it is suggested that the surface speed off the condenser drum be of the order or 120 feet per minute, it has been found that in 'the oper'ation of 'the present apparatus a condenser drum surface speed ofapproximately 7'6 "feetper minute insures ahetter distribution of the flint upon "the drum surface, and a :consequent better and more uniform ,preseiitation of the lint to the saw cylinder. I

I To obtain optimum results in the combing and cleaning of the lint, it is necessary, so far possible, to minimize the.space betvve'en the tips of thesaiw-cylinder teeth and that grid bar, at least, which is nearest to thepoint at vvhich the flliiit is delivered to the saw cylinder; but,.=s ince thesavv cylinder is of substantial length hetweenits bearflags and "rotates at high speed, and becauseihardllumpsod material sometimes enter;between the saw cylinder and bar, it has been found impractical lheretotore to space the first grid bat-less than Q37 to Q0 8Dinch from the geometrical cylinder (theoretically defined by1-the tips of the rotating teeth) because the springing of the saw cylinder or the bending of the grid :bar, it ialesser clear-- ance isa'ttempted, results in contact offthe teeth with the liar, eausing serious mechanical injury to the parts andeven at times starting a fire .in the apparatus. One object of the present invention is Improvide an improved saw cylinder, which may be of the customary outside dimensions, and which may be driven at the desired surface speed, but which .is so resistant to springing out of truecylindrical form that it is possible to reduce the space between the tips of the saw teeth and the first grid sbar to approximately one-half the customary spacing;

Eln the apparatus disclosed in the above copend'mg ap- U ited States Patent 1C6 a 2,948,022 Patente'd Air-g. 9, "1960 ,2 {tines-hen (=asactua -lly cbnstructed) aipa'ir of'dofier rolls, 'inehe sjand fi inches respectively in diameter, interp sea between the condenser drum and a toothed teed 16-11 or apfiroitirnately 3 inches in outsidediameter which at a distance or "the order or 0:635 to 0:040 inch with 'As'a eecondary result'of theeirnploym-entdf the "larger feed roll, it beco mes possible to dispense vvith the two adheres-ins, the feed r011 itself acting to 'doif the iint from the cohiienser "The elimination of the two dofier toils siihs'tantially "reduces the cost of the ap aratus, for exe e "as mnch '4 or 5 percent.

fltefieve'rlint *tt'on "is carried through a conduit or passage by an current, the presence otf any imperfect'ron'or roughness in the surface of the duct, even though very minute, provides an manor-ag tier one or more fibers, and to these first few attached "fibers others "cling until a long streamer *is formed. Because of the action of the moving current, such *a streamer often twist so that eventually it becomes hard and rope-like. When such a massed? fiber becomes heavy enough, itwill tear sway *homt-he "hit of anchorage ahd'travel along as a dense e'r wad with the current. When such a hardmass or ad of fih'ersiis caught by the teeth of the rotating saw cylinder, in a e1 anin'g ap aratus "(if the kind to which the present invention relates, it may become jammedb'etvveen the cylinder and "the fid her, som times resulting in a severe smash, requiring a renewal (if the saw cylinder at grid bar.

In'theappai atus o f the above'coiiending application, a guard bar is associated with the feed roll, this guard ba'r having a concave surface opposed-totheteeth of 'the' feed toil, hut s aced therefrom. This "guard baiprevents loose lint, not firmly embedded in the teeth of the feed roll, from being-ejected by centrifugal force before it reaches the teeth ofthesaw cylinder, thus insuringthat all of the lint enters "the space between the feed ro'll and this guard bar vvill ultimately be caught by the teeth of the saw cylinder and will not be discharged in uncleaned condition into the stream of :air leaving the cleaning apparatus. In accordance with the present invention, there is provided a guard bar having functional characteristics general-1y like those of the bar just above-described, but which is made suhiciently heavy to Withstand force exerted against 'it 'by wads of cotton caught between it and the feed $011. In accordance with one embodiment of the invention, the concave surface of this bar is provided vvith means,- forexamp le ribs or teeth, which act to abrade any such hard mass of cotton fiber as it is carried along by the feed roll, so that such mass will be torn up and disintegra'ted. In order to insure such action so far possible, this guard bar is of substantial vertical depth so that its concave toothed surface may be of an arcuate length ot the order of four inches. I

As a further precaution to avoid damage to the apparatus the event that such a hard mass of material enter between the .feed roll and .guard bar, or between the saw cylinder and one of the grid bars, the apparatus, in accordance with the present invention, is vprovided with a friction clutch in the drive connections to prevent any such hard mass of material from causing breakage of the machine parts. With such an arrangement, and by using a large diameter and rigid saw cylinder, and by making the first grid bar strong and rigid, the possibility of damage to the apparatus from the presence of hard lumps of material is minimized. While in the apparatus of the above application the guard bar, which cooperates with the feed roll is so located that the upgoing teeth of the saw cylinder approach the underside of this guard bar and the feed roll turns oppositely to the saw cylinder, and although in one embodiment of the present invention a similar location of the guard bar is contemplated, there is a preferred construction in accordance with the present invention, in which the guard bar is located at the opposite side of the feed roll, that is to say, it is so located that the down-going teeth of the saw cylinder pass beneath the lower edge of the guard bar, and the feed roll is caused to turn in the same direction as the saw cylinder. In this latter arrangement, the guard bar is so arranged that the passage.

between its concave surface and the periphery of the feed roll gradually decreases in width radially of the feed roll, while the passage between the lower side of this guard bar and the tips of the down-going teeth of the saw cylinder gradually increases. Preferably, provision is made for varying the exit end of this latter passage, thereby to vary the amount of cleaning which occurs at the first grid bar. Other desirable features and objects of the invention will be pointed out in the following more detailed description and by reference to the accompanying drawings wherein:

Fig. 1 is a vertical section, more or less diagrammatic and omitting parts, in a plane perpendicular to the axis of the carding roll, illustrating one embodiment of the present invention;

Fig. 2 is a fragmentary vertical section, to larger scale than Fig. 1, but in the same vertical plane, showing in greater detail the carding roll and associated guard bar and showing portions of the screen drum and saw cylinder; the latter being shown as provided with Garnett type teeth in lieu of the usual saw teeth.

Fig. 3 is a view similar to Fig. 2, but illustrating a modification;

Fig. 4 is a fragmentary elevation showing the toothed or ribbed face of the guard bar illustrated in Figs. 2 and 3; and

Fig. 5 is a fragmentary view, showing an arrangement generally similar to Fig. 2, but illustrating a guard bar of a modified construction.

Referring to the drawings, the character C (Fig. 1) designates the cleaner as a whole, this cleaner com prising a casing, usually of sheet metal, having an upper section which may, for convenience, be referred to as the condenser section and which defines a chamber 11 having an inlet opening 12 to which there is connected the delivery end of a duct 13 which leads from a gin stand, not shown. Within the chamber 11, there is arranged a cylindrical condenser or screen drum 15 mounted on a shaft 16 suitably journaled at its ends in bearings, not shown, supported by the casing. The periphery of this screen drum may be of any conventional material, for example, perforated sheet metal or wire cloth suitably supported to provide a cylindrical surface on which the lint, which enters the chamber 11, may deposit as a thin layer. The opposite ends of the condenser or screen drum 15 are arranged closely a-djacent to the opposite end walls of the casing 10 with usual provisions for avoiding air leakage between the ends of the drum and the casing, and the ends of the drum open into suitable chambers from which passages lead to an air duct D which is connected to a suction fan (not shown) of sufficient capacity to withdraw substantially all of the air which, entering through the duct 13, passes inwardly through the perforate screen drum 15 and out through the open ends of the latter. Suitable manually actuable valves (not here shown) may be provided for controlling the effective size of each of the passages respectively which lead from the open ends of the condenser drum to .the air duct D, thereby to control the effective suction in the duct leading from the gin stand, this being desirable when a battery of gin stands is served by the same suction fan. However, this arrangement of valves is no part of the present invention.

Below the chamber 11, the casing is shaped to provide the cleaning chamber 17 within which is mounted, the saw cylinder 18 having a shaft 18 which is journaled at its opposite ends in suitable bearings, not shown, supported by the casing. This saw cylinder may be substantially like the conventional gin saw cylinder in construction, as indicated in Fig. 1, although it is preferred to employ a saw cylinder comprising a very rigid tubular core K of steel, having a wall thickness of approximately /2" and an outside diameter of approximately 11%" and which may form a support for Garnett type saw teeth or for annular saw blades with interposed spacers.

Grid bars 19, 19 19* etc. are arranged in cooperating relation to the periphery of the saw cylinder, the inner edges of these bars being spaced at short distance from the tips of the saw teeth and operating, as is customary in apparatus of this type, to knock dirt and trash out of the lint as the latter, carried by the teeth of the saw cylinder, is whipped past the bars as the cylinder rotates.

The first three of these bars Fig. 1, indicated at 19, 19 19 respectively, are thicker than is customary and have inner arcuate faces approximately concentric with the saw cylinder, and upper substantially flat faces which intersect said arcuate faces to form acute edges, parallel to the axis of the saw cylinder and directed upwardly toward the down-coming saw teeth. As here illustrated, the flat upper face of each of the bars '19, 19 and 19 is inclined at approximately 40 to a radial plane through the acute edge of said bar. In a preferred arrangement, the acute inner edge of the first or upper grid bar 19 is above a horizontal plane through the axis of the saw cylinder and in a radial plane which makes an angle of 25 with the horizontal; the edge of the second grid bar 19* is in a radial plane which makes an angle of 18 below the horizontal; and, the edge of the third grid bar 19 is in a radial plane which makes an angle of 43 below the horizontal. The lower bars 19, 19 and 19 are shown as substantially rectangular in transverse section and disposed in approximately radial relation to the saw cylinder. The several bars are mounted at their opposite ends in adjustable brackets 20 carried by the end walls of the casing, but normally these bars are stationary. Since as above described, the saw cylinder is unusually rigid and runs true, it is desirable to make the first or upper grid bar, at least, very rigid. Thus, it may, as illustrated, be of the order of 1% in maximum thickness and of a maximum depth of the order of 3", and, being so rigid, its edge may be spaced from the path of the saw teeth not more than. from 0.035" to 0.040".

At the rear of the saw cylinder, there is arranged a rotating doffer brush 22 mounted on a shaft 23. The brush turns oppositely to the saw cylinder and has a per ripheral surface velocity exceeding that of the saw cylinder, for example a surface velocity of 7,000 feet per minute. Running at this velocity, the brush acts as a fan, generating an air current suflicient to carry the lint, after removal from the teeth of the saw cylinder, through the conduit 30 to a battery condenser. The brush is so arranged that its bristles reach substantially to the roots of the teeth of the saw cylinder. This brush is housed in a chamber 24 defined at its top by an upper wall 25 which is spaced from the lower wall 26 of the passage 12 to provide a channel 27 through which atmospheric air may enter freely and flow toward the periphery of the saw cylinder. The wall 25 terminates at *25 a short distance, for example 1% inches from the periphery of the .saw cylinder, and is spaced from the periphery or the brush 22 to provide a delivery passage .28 leading-to the outlet 29 from which the conduit 30 leads to the battery condenser. The lower wall 20 of the brush chamber 24 .is approximately concentric with the brush, being united at its forward end at :20 to the rear wall 56 of the chamber 17 and .at .its opposite edge .to the outer wall W of the casing. Between theedges 25 .and .20 the saw cylinder is exposed to the'brush so that the Jim carried by the teeth of the saw cylinder may be defied by the brush, the lint being swept away from the .saw cylinder "by :the air current generated-by the brush and delivered to the outlet 29 as above described.

Immediately below the screen down 15, a .feed .roll or combing or carding cylinder 46 is :arranged. This comb- .ing cylinder or roll is desirably of the order of 7% inches external diameter; Its peripheral surface may .be formed of a layer of card clothing of conventional type but, preferably, as herein illustrated, the pins or teeth .of this card clothing project radially outward instead of being inclined as is the more customary arrangement. The toothed covering material is attached to the peripheral surface of a rigid, cylindrical core desirably formed from steel tubing and having a wall thickness of approximately /2' inch carefully turned to provide an accurate cylindrical surface. This cylindrical core is provided at its opposite ends with trunnions, one of which is indicated at 47, which turn in bearings, not shown, car- .ried by the casing. Using a carding .roll of the diameter suggested, it is desirably driven at a speed of 100 rpm. Gne of the trunnions is of .suflicient length to .receive a driving element, for instance a sprocket or .gear.

.As shown in the drawings, the axis of the combing cylinder 46 is offset to the right of the vertical plane through the axis of the screen drum 15. In actual practice, the vertical planes through the axes of the roll 46 and screen drum are approximately two and one-half inches apart. With this arrangement, the distance between the peripheries of the screen drum and the carding cylinder, at their point of near tangency, is approximately one quarter of an inch. With this spacing, the carding cylinder acts as .a doffer to take lint directly from the surface of the screen drum, thus eliminating the deffor roll or rolls commonly employed in apparatus of this .general type.

As illustrated in Figs. .1 and 2, a rigid bar 41 is just to the right of the combing roll 46. The bar 41 extends the full length of the combing .roll 46 and is fixedly at- .tached at its opposite ends to t hecasing.

The lower margin of the casing 10 is fixedly connected to the upper part of the bar '41, the-latter having an up wardly concave lower surface 43 .(Fig. 2) whose radius of curvature may, for example be six and three-eighths inches, whereas the radius of curvature 'of saw cylinder .18 is approximately six inches. The surface 43 is eccentric to thesaw cylinder so that the passage P between the surface 43 and the path of the tips of the saw teeth increases from its entrance end, where its width is one-sixteenth of an inch, towards its delivery end, where it is approximately one-quarter of an inch in width.

The rear or inner surface of the bar 41 (as viewed in Fig. 2) is concave and of a radius of curvature of approximately three and thirty-one-t'hirty-seconds of an inch, as compared with a radius of curvature of the combing roll of three and three-quarters of an inch, but the center of curvature of the concave surface of bar 41 is located approximately five-sixty-fourths of an inch above the axis of the roll 46 so that the lint-guiding passage 52 between the bar 41 and the tips of the saw teeth tapers downwardly .in width, being approximately seven-thirtyaseconds of .an inch in width at its upper or entrance end, and approximately one-eighth of an inch in width at "its lower or delivery end. The lower surface 43 of the bar 41 intersects the rear or inner concave suriace of the Ibarat a smoothly rounded edge E, the circumferential width of :the concave surface 43 being such thatit extends .from the point B downwardly .to a point appoximately 45 from the vertical ,plane to theaxis of the saw :shaft. .In order to .reducethe size of or to disintegrate lumps or wads of ilint which may enter the wider, upper end .of the passage "52, the surface of the concavity .in the bar '41 may .be ,provided' with longitudinally extending ribs 44 (Fig. 4) or with rigid teeth of any desired configuration so that, in cooperation with the pins of-the carding cylinder 46 this rough surfaced concavity acts like a grater .to :scruband abrade any lumps or wads and thus reduce them to a size such that they may pass through the smaller end of the lint-guiding passage and between the combing cylinder and saw without causing damage to the machine parts. 7

At the opposite side of the combing cylinder 46 from the bar 41, the forward margin of the casing member 26 attached, [for example by welding to a flange 26 of a sheet metal guard device having an upwardly directed portion "26 which terminates in .a rounded edge 39 spaced approximately one-quarter of an inch fro-m the peripheral surface of the screen drum .15. This guard device also comprises a portion 26 which extends downwardly in substantially concentric relation to the combing roll 46 and spaced from the surface of the latter to provide a clearance of approximately one-quarter of an inch and terminates in a flange member 26 which is spaced from the tips of the saw teeth a distance of approximately onequarter of an inch. The clearance between the "edge 39 and the surface of drum 15 permits any lint, which may .not be removed from the drum 15 by the roll;46, to continue along on the surface of the drum, thus avoiding the formation of wads of lint in the angle between the flange 26 and the drum.

The lower part of the casing of the cleaner (-Fig. 1-) is of hopper shape comprising the downwardly diverging walls 55 and 56 which lead to a channel having a floor formed by the upper run 57 of an endless belt which receives the dirt and trash which falls from the bars 19, 19 etc. and carries it out through an opening (not shown) in the end wall of the casing. This same belt, if desired, .may extend along an entire battery of cleaners 'so as to receive refuse from each in turn. For good results, and as an example of desirable relative sizes of certain of the parts, the diameter of the saw cylinder may be eleven and three-fourths inches, the diameter of the combing cylinder 46 may be seven and one-half inches; the peripheral surface speed of the saw cylinder 18 may be of the order of 2,000 feet per minute; the surface feed of the doifer brush cylinder 22 may be of the order of 7,200 feet per minute; the surface feed of the combing cylinder 46 may be of the order of 240 feet per minute; .and, the condenser drum 15 may have a surface speed of approximately 76 feet per minute.

It will be noted (Fig. 2) that the terminal end of the lint-guiding passage 52 .is near the vertical plane through the axes of the combing roll 46 and saw cylinder 18, for instance, .a distance of approximately one inch and, as ,above described the passage P extends from edge E about the periphery of the saw cylinder to a point approximately 45 from the vertical plane through the axis of the saw cylinder. With this arrangement, the lint which moves downwardly through the lint-guiding passage 52 is kept in contact with the toothed surface of the carding cylinder through a long arc, for example more or less; and, since the width of the passage "gradually decreases the lint is subjected throughout the entire length of the passage to a combing operation for a sutficiently long time to insure optimum smoothing and paralleling of the fibers.

Desirably, there is provided at the lower part of the bar 41 an adjustable plate N (Fig. 2.) having a rounded edge directed towards the saw teeth. This plate may be adjusted up or down. By changing the positio'n of this member N, the effective width of the passage P, at its terminal end,.may be varied, for example from one-six teenth of an inch to one-quarter of an inch. By thus adjusting this member N, the amount of throw-off at the first grid bar 19 may be varied. If less cotton loss is desired at the expense of cleaning, the edge of member N is set close to the saw cylinder; but, if maximum cleaning is desired at the expense of a slightly greater amount of throw-off, then the width of the passage P, at its terminal portion, may be increased to the maximum onequarter of an inch.

The drive connections for the screen drum 15 and carding roll 46 desirably comprise a slip-clutch, which may be of any conventional or desired type. For instance, a clutch such as is sold by Morse Chain Company of Houston, Texas, under the name Torque Limiter may be interposed between the power source and the sheave which drives the several rotating parts of the cleaner. By the use of such a slip-clutch between the driving and driven parts, the jamming of wads of lint between the rotating members and adjacent parts, for example between the carding roll and guide bar will not result in breakage of parts.

While the arrangement hereinabove described is useful, a modified construction is illustrated in Fig. 3. The modified apparatus, thus shown, is in general like that above described, comprising a casing which defines a chamber 11 in which the screen drum 15 is located; the carding cylinder 46; the saw cylinder 18; and, a dofier brush (not shown in Fig. 3) like the brush 22 illustrated in Fig. 1. The casing comprises a part 26 which forms the lower wall of a flue through which the lint-carrying air current enters the chamber in which the condenser drum 15 is housed.

In this modification, the carding cylinder 46 turns in opposition to the saw cylinder and a rigid bar 41* (generally corresponding in structure and function to the bar 41 above described) is arranged to the left of the carding roll, as viewed in Fig. 3, that is to say, at the opposite side of the carding roll as contrasted with the position of the bar 41 of Figs. 1 and 2. This bar has an upper surface 42 (Fig. 3) desirably provided with a shallow rabbet in which the forward margin of the casing wall 26 is secured. At its forward part, the upper surface of the bar is shaped to provide an upwardly directed rib 42* having a smoothly rounded upward edge which is spaced approximately one-quarter of an inch from the periphery of the screen drum 15. The righthand face of the bar 41 has a longitudinally extending shallow concavity, of a radius of curvature of approximately seven and twenty-one-thirty-seconds inches, that is to say, its radius of curvature exceeds that of the combing or carding roll by approximately seven-thirty-seconds of an inch. Preferably, the center of curvature of this concavity in the guard bar is eccentric with respect to the axis of the roll 46 so that the lint-guiding channel 52*, between the bar and the surface of the roll, tapers downwardly from a relatively wide upper end toward its lower end, the latter end being closely adjacent to the periphery of the saw cylinder. Desirably, the lower end of this channel 52 is of a fixed width of approximately oneeighth of an inch.

To provide for such a downwardly tapering channel, the center of the curvature of the concavity of the bar may be located five-sixty-fourths of an inch above the axis of the roll 46. To provide the requisite rigidity, the bar -41, which may be an aluminum extrusion, may be of a right-to-left thickness, between the surfaces a and b, of approximately two and three-fourths inches, and of a maximum depth of approximately seven and three-eighth inches.

As shown in Fig. 3, the lower portion 45 of the curved forward surface of the bar 41 is devoid of ribs or teeth and is substantially concentric with the carding or ,combing roll 46 while the surface. of the concavityiis erably by wrapping its margin about a bar 40 which extends from one side of the machine to the other.

bar, with the terminal portion of the casing wall, is here illustrated as being spaced approximately A1, inch from the peripheral surface of the combing cylinder 46.

A horizontal shaft 53 has its axis in a radial plane of the saw cylinder about 16 above the radial plane through the acute edge of the upper grid bar 19. This shaft 53 supports a lint guard G, here shown as coniprising a hollow sheet metal shell having a concave inner wall 54 and an outer wall 55, with a stiffening rod 56 at its upper edge where the inner and outer walls merge. The upper edge of this guard is normally disposed approximately /2 inch from the up-going portion ofthe peripheral surface of the combing cylinder 46, while the inner surface of the wall 54 at its lowest point is spaced from the tips of the saw teeth approximately /8 inch. Normally, the inner wall 54 of this guard diverges upwardly and away from the saw cylinder. To give access to the, saw cylinder at this point, the guard G is preferably so mounted on the shaft 53 that it may be tumed outwardly and away from the saw cylinder. The guard G is operative to prevent lint which is not firmly caught by the saw teeth from escaping before it reaches the grid bar 19. Any lint which is not adequately embedded in the saw teeth and which flies off from the teeth at this point is recaptured by the guard G and returned to the saw cylinder at the lower edge of the guard. If the guard device G were not used, a considerable amount of lint might be thrown off from the saw cylinder at the point where the feed roll or combing cylinder 45 delivers the lint to the saw cylinder. If the shaft 53 which supports the guardwere to be located substantially closer to the top grid bar 19, then, as above described, the moting action of the top grid bar would be substantially reduced. Thus, the particular location of the guard G, as above described, is important in order to minimize the loss of use:- ful lint; while, at the same time, to obtain the maximum moting effect.

In the arrangement illustrated in Fig. 5, all of the parts, except for the guard bar, are like those of Fig. 2. and are designated by the same reference characters The guard bar 41 of Fig. 5 is devoid of the ribs or teeth 4-4 shown in Fig. 2, its main concave surface 44 being smooth. Moreover, the edge E, at which the concave inner surface 44* intersects the lower concave surface 43 is located closer to the vertical plane of the axes of the combing roll and saw cylinder than in the arrangement of Fig. 3, for instance a distance of the order of one-half inch. This type of guard bar does not exert any abrading action upon the lint, and may be preferred under some conditions, particularly when little trouble is experienced from the formation of lumps.

While certain embodiments of the invention have herein beendisclosed by way of example, and while dimensions have been cited as suggestive of relationships which have been found in practice to insure desirable results, it is to be understood that the specific mechanism and such suggested dimensions are made by way of illustration, and that all modifications within the scope of the appended claims are considered to be within the purview of the invention.

I claim:

1. In a cotton lint cleaner wherein the cleaning instrumentalities include a rotatable saw cylinder and spaced grid bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screen drunt This g whose axis is parallel to that of the saw cylinder, and on whose peripheral surface the lint to be cleaned is pneumatically deposited as a thin layer; in combination, a toothed carding cylinder turning about an axis parallel to the axes of the screen drum and saw cylinder with its toothed periphery closely adjacent, at circumferentially spaced points, to a tangent to the screen drum and to a tangent to the saw cylinder respectively, said toothed cylinder being driven at such a linear velocity and in such a "direction as to dofl. lint directly from the screen drum and to deliver it directly to the teeth of the saw cylinder, said toothed cylinder constituting the sole mechanical means for transferring lint from the :screen drum to the saw cylinder.

2. A drum lint cleaner, according to claim 1, wherein the toothed carding cylinder is of the order of 7.5 inches in outside diameter and the saw cylinder has a rigid tubullar steel core of a wall thickness of the order of 0.5 inch and an external diameter of the order of 11.75 inches.

3. In a cotton lint cleaner wherein the cleaning instrunnentalities include a rotatable saw cylinder and spaced grid bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screen spasms drum whose axis is parallel to that of the saw cylinder,

and on whose peripheral surfiace the lint to be cleaned is pneumatically deposited as a thin layer; in combination, a toothed carding cylinder turning about an axis parallel to the axes of the screen drum and saw'oylinder with its toothed periphery closely adjacent, at circumferentially 'spaced points, to a tangent to the screen drum and to a tangent to the saw cylinder respectively, said toothed cylinder being driven at such a linear velocity and in such a direction as to doff lint directly from the screen drum and to deliver it directly to the teeth of the :saw

cylinder, and having guard means spaced from but extending about the carding cylinder through an arc of approximately 90, said guard means being operative :to prevent centrifugal expulsion o-flint from the periphery of the carding cylinder.

4. In a cotton lint cleaner wherein the cleaning instrumentalities include a rotatable saw cylinder and spaced grid bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screen drum whose axis is parallel to that of the saw cylinder, and on whose peripheral surface the lint to be cleaned is pneumatically deposited as a thin layer; in combination, a toothed carding cylinder turning about an axis parallel to the axes of the screen drum and saw cylinder with its toothed periphery closely adjacent, at circumferentially spaced points, to a tangent to the screen drum and to a tangent to the saw cylinder respectively, said toothed cylinder being driven at such a linear velocity and vin such a direction as to doff lint directly from the screen drum and to deliver it directly to the teeth of the saw cylinder, said toothed cylinder constituting the sole mechanical means for transferring lint .from the screen drum to the saw cylinder, and a rigid elongate bar extending parallel to the axis of the toothed carding cylinder, and which has a concave arcuate surface opposed to the periphery of the carding cylinder, but spaced from the latter to provide a lint passage between them, said passage tapering in width with its narrower end closely adjacent to the path of the tips of the teeth of the saw cylinder.

5. In a cotton lint cleaner wherein the cleaning instrumentalities include a rotatable saw cylinder and spaced grid bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screen drum whose axis is parallel to that of the saw cylinder, and on whose peripheral surface the lint to be cleaned is pneumatically deposited as athin layer; in combination; a toothed carding cylinder turning about-an axis parallel to the axes of the screen drum and saw cylinder with its a tangent to the saw cylinder respectively, said toothed cylinder being driven at such a linear velocity and in such a direction as to doff lint directly from the screen drum and todeliver it directly to the teeth of the saw cylinder, said 'toot'hed cylinder constituting the :sole mechanical means "for transferring lint from the screen drum to the saw cylinder, and wherein the carding cylinder and saw cylinder turn in opposite directions, and the rigid baris arranged at that side of the carding cylinder toward which the up-going teeth of the saw cylinder are moving.

6. In a cotton lint cleaner wherein the cleaning instrumentalities include a rotatable saw cylinder and spaced "grid 'bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screendrum whose axis is parallel to that of the saw cylinder, and on whose peripheral surface the lint to be cleaned is pneumatically deposited as a thin layer; in combination, a toothed carding cylinder turning about an axis parallel to the axes of the screen drum and saw cylinder with its toothed periphery closely adjacent, at circumferenti-a'lly spaced points, to a tangent to the screen drum and 10 8. tangent to the saw cylinder, respectively, said toothed cylinder :being driven at such a linear velocity and in such a direction as to doff lint directly from the screen drum and to deliver it directly to the teeth of the saw cylinder, said toothed cylinder constituting the sole mechemical means for transferring lint from the screen drum to the saw cylinder, a rigid elongate bar extending parallel to the axis of the toothed carding cylinder, and which has a concave arc-uate surface opposed to the periphery of the carding cylinder, but spaced from the latter to provide a lint passage between them, said passage tapering in width with its narrower end closely adjacent to the path of the tips of the teeth of the saw cylinder, wherein the concave arcuate surface of the rigid bar is roughened to provide abrading elements operative to disintegrate lumps of cotton lint interposed between the bar and the carding cylinder.

7. In a cotton lint cleaner wherein the cleanin'g'instrumentalities include a rotatable saw cylinder and spaced grid bars arranged about an arc of the peripheral surface of the saw cylinder, and having a rotating screen drum whose axis is parallel to that of the saw cylinder, and on whose peripheral surface the lint to be cleaned is pneumatically deposited as a thin layer; in combination, a toothed carding cylinder turning about an 'axis parallel to the axes of the screen drum and saw cylinder with its toothed periphery closely adjacent, at circumferentially spaced points, to a tangent to the screen drum and to a tangent to the saw cylinder respectively, said toothed cylinder being driven at such a linear velocity and in such a direction as to doif lint directly from the screen drum and to deliver it directly to the teeth of the saw cylinder, said toothed cylinder constituting the sole mechanical means for transferring lint from the screen drum to the saw cylinder, a rigid elongate bar extending parallel to the axis of the toothed carding cylinder, and which has a concave arcuate surface opposed to the periphery of the carding cylinder, but spaced from the latter to provide a lint passage between them, said passage tapering in width with its narrower end closely adjacent to the path of the tips of the teeth of the saw cylinder, and wherein the arcuate surface of the rigid baris provided with a plurality of parallel rigid ribs operative to abrade lumps of lint carried along by the teethof the carding cylinder.

8. In a cotton lint cleaner of the kind to which lint is conveyed from a gin by an air current and which comprises a casing having therein a rotary condenser drum toothed periphery closely adjacent, at circum-ferentially on whose surface the lint is deposited as a thin layer while the major portion of the conveying air is being separated from the lint, and cleaning instrument-alities including a rotating saw cylinder whoseaxis is parallel to that of the condenser drum, spaced-parallel gridbars arranged about an arc of the peripheral surface of the saw cylinder, and means for dofiing cleaned lint from the teeth of the saw cylinder, in combination, a carding cylinder turning about an axis parallel to the axis of the saw cylinder, said carding cylinder having a peripheral surface to which lint tends to adhere, the carding cylinder being so located, relatively to the condenser drum and saw cylinder, as to doif lint directly from the condenser drum and to deliver it directly to the teeth of the saw cylinder, and means extending about an arc of the carding cylinder, but spaced from the peripheral surface of the latter, to define, with said carding cylinder, a lint-guiding passage whose terminus is closely adjacent to the path of travel of the tips of the teeth of the saw cylinder, and wherein the means which cooperates with the carding cylinder to define the lint-guiding passage is located above that part of the saw cylinder at which the teeth of the saw cylinder are moving upwardly.

9. In a cotton lint cleaner of the kind to which lint is conveyed from a gin by an air current and which comprises a casing having therein a rotary condenser drum on whose surface the lint is deposited as a thin layer while the major portion of the conveying air is being separated from the lint, and cleaning instrumentalities including a rotating saw cylinder whose axis is parallel to that of the condenser drum, spaced parallel grid bars arranged about an arc of the peripheral surface of the saw cylinder, and means for dofiing cleaned lint from the teeth of the saw cylinder, in combination, a carding cylinder turning about an axis parallel to the axis of the saw cylinder, said carding cylinder having a peripheral surface to which lint tends to adhere, the carding cylinder being so located, relatively to the condenser drum and saw cylinder, as to dotf lint directly from the condenser drum and to deliver it directly to the teeth of the saw cylinder, and means extending about an arc of the carding cylinder, but spaced from the peripheral surface of the latter, to define, with said carding cylinder, a lint-guiding passage whose terminus is closely adjacent to the path of travel of the tips of the teeth of the saw cylinder, wherein the means which cooperates with the carding cylinder to define the lint-guiding passage is a rigid bar having a concave, arcuate rear surface spaced from the periphery of the carding cylinder and forming one wall of said passage, said bar being located above that part of the saw cylinder at which the teeth of the saw cylinder are moving downwardly, the bar having a concave, arcuate bottom surface eccentric to the saw cylinder and defining a delivery passage whose width increases from its upper end, where it is adjacent to the periphery of the carding cylinder toward its lower end where said bottom surface terminates at an edge which is approximately 45 from a vertical plane through the axis of the saw cylinder.

10. A cotton cleaner, according to claim 9, wherein the passage between the rigid bar and the saw cylinder is of a width of approximately of an inch at that end which is the closer to the carding cylinder.

11. A cotton cleaner, according to claim 9, wherein the two concave surfaces of the rigid bar merge in a rounded edge spaced a distance of the order of one-half inch from a vertical plane through the axis of the saw cylinder in the direction in which the saw teeth are moving, and the carding cylinder turns in the same direction as the saw cylinder.

12. A cotton cleaner, according to claim 9, wherein means is provided for adjusting the width of the delivery end of the passage between the concave bottom surface of the rigid bar and the periphery of the saw cylinder.

13. In a cotton cleaner of the kind which comprises a rotary saw cylinder, a plurality of spaced, parallel grid bars arranged about an arc of the peripheral surface of the saw cylinder, a condenser drum on whose peripheral surface lint is deposited as a thin layer while the major portion of a lint-carrying air current is being separated from the lint, in combination, a toothed carding cylinder and condenser drum, said toothed carding cylinder being of such a diameter and having its axis so located that spaced points in the periphery of the carding cylinder are so close to tangents to the condenser drum and saw cylinder, respectively, that the carding cylinder acts to doff lint directly from the condenser drum and to deliver it directly to the teeth of the saw cylinder, means operative to keep the lint, removed from the condenser drum, within the field of action of the said carding cylinder along an arc of the latter cylinder exceeding and for keeping the lint within the field of action of the saw cylinder through an arc of its periphery of approximately 45.

14. A cotton lint cleaner, according to claim 13, wherein the means for keeping the lint within the fields of action of the carding cylinder and saw cylinder comprises a rigid bar having a concave surface which is opposed to but spaced from the peripheral surface of the carding cylinder, and a second concave surface which is opposed to but spaced from the periphery of the saw cylinder, said concave surfaces meeting at an edge which is located within the dihedral angle defined by the peripheries of the carding cylinder and saw cylinder, said edge being spaced, in the direction of movement of the saw teeth, from a vertical plane through the axis of the saw cylinder.

15. In a cotton cleaner of the kind which comprises a rotary saw cylinder, a plurality of spaced parallel grid bars arranged about an arc of the peripheral surface of the saw cylinder, a condenser drum on whose peripheral surface lint is deposited as a thin layer while the major portion of the lint-carrying air current is being separated from the lint, in combination, a toothed carding cylinder arranged to turn about an axis which is parallel to the axes of the condenser cylinder and the saw cylinder, said toothed carding cylinder being of such dimensions and turning about an axis so located that spaced points in the periphery of the carding cylinder are so close to tangents to the condenser drum and saw cylinder, respectively, that the carding cylinder acts to dolf lint directly from the condenser drum and deliver it directly to the saw cylinder, a rigid guard bar having a surface which is opposed to but spaced from the periphery of the carding cylinder, said guard bar being located above the first of the grid bars which is engageable by lint carried by the down-going teeth of the saw cylinder, said guard bar being so shaped as to provide a passage extending about the carding cylinder through an arc of approximately and which, at its upper end, is of a width of approximately of an inch and which, at its lower end, is normally of a width of approximately of an inch, the guard bar also being shaped to provide a passage extending about the saw cylinder through an arc of approximately 45, and which, at its upper end, is approximately of an inch in width, and, at its lower end is approximately of an inch in normal width, the lower end of said latter passage being spaced approximately 20 of are from the first of said grid bars.

16. In a cotton cleaner of the kind which comprises a rotary saw cylinder, a plurality of spaced parallel grid bars arranged about an arc of the peripheral surface of the saw cylinder, a condenser drum on whose peripheral surface lint is deposited as a thin layer while the major portion of the lint-carrying air current is being separated from the lint, in combination, a toothed carding cylinder arranged to turn about an axis which is parallel to the axes of the condenser drum and the saw cylinder, said carding cylinder being of such dimensions and turning about an axis so located that spaced points in the periphery of the carding cylinder are so close to tangents to the condenser drum and saw cylinder, respectively, that the carding cylinder acts to doif lint directly from the condenser drum and deliver it directly to the saw cylinder, and means cooperable with the saw cylinder to keep the lint in close proximity to the periphery of the saw cylinder through an arc of approximately 45 meas 13 ured in the direction of motion of the saw teeth from a point at which the lint is first delivered to the saw cylinder by the carding cylinder.

17. In a cotton cleaner of the kind which comprises a rotary saw cylinder, a plurality of spaced parallel grid bars arranged about an arc of the peripheral surface of the saw cylinder, a condenser drum on whose peripheral surface lint is deposited as a thin layer while the major portion of the lint-carrying air current is being separated from the lint, in combination, a toothed carding cylinder arranged to turn about an axis which is parallel to the axes of the condenser drum and the saw cylinder, said carding cylinder being of such dimensions and turning about an axis so located that spaced points in the periphery of the carding cylinder are so close to tangents to the condenser drum and saw cylinder, respectively, that the carding cylinder acts to doif lint directly from the condenser drum and to deliver it directly to the saw cylinder, a guard which cooperates with the saw cylinder to define a passage extending from a point adjacent that at which the lint is first deposited on the saw cylinder by the carding cylinder, said passage being of a length of approximately 45 about the periphery of the saw cylinder, the lint being carried by the saw teeth through said passage, the passage being of greater width (measured radially of the saw cylinder) at its delivery end than at its receiving end.

18. A cotton cleaner, according to claim 17, wherein the passage between the guard and saw cylinder is of a width approximately 5 of an inch at its receiving end and of a normal width of approximately A of an inch at its delivery end, and adjustable means for varying the efiective width of the passage at its delivery end.

19. In cotton lint-cleaning apparatus of the kind which comprises a foraminous condenser which acts to separate the major portion of the air from a lint-carrying air current and on which the separated lint is deposited as a thin layer, and cleaning instrumentalities including a saw cylinder, a plurality of spaced parallel grid bars arranged about an arc of the periphery of the saw cylinder and means for doffing cleaned lint from the teeth of the saw cylinder, in combination, a toothed cylinder having a surface to which lint tends to cling and which turns about an axis parallel to that of the saw cylinder, said toothed cylinder being so constructed and arranged as to doff lint directly from the condenser and to deliver it directly to the teeth of the saw cylinder, and means cooperating with the toothed cylinder to disintegrate lumps of lint which contact the surface of the toothed cylinder, wherein the means for disintegrating lumps of lint comprises a rigid bar having a concave surface opposed to but spaced from the periphery of the toothed cylinder and which cooperates with the roll to define a lint-guiding passage, said passage being of decreasing width radially of the toothed cylinder from its receiving end to its delivery end, said concave surface being provided with protuberances operated to abrade lumps of lint as they are moved through the passage by the toothed cylinder.

References Cited in the file of this patent UNITED STATES PATENTS 1,173,978 Johnston Feb. 29, 1916 1,239,432 OConnell Sept. 4, 1917 2,711,381 Novotny et al. June 21, 1955 2,747,235 Wallace May 29, 1956 2,755,512 Moss July 24, 1956 

